Hi Hartmut,

Yes turning off the speaker did solve the failed moves I faced.
I run a quite old HP620 laptop (2 cores x 2,1Ghz), the computing power is enough for the usage I have, but it is quite limited elsewhere, including display performance and sound as well. I guess I have sort of a bottleneck for playing sounds ; mostly if several processes want to, at the very same time, and causing some lag in the executed process.
Indeed the first time I had this issue was a tournament game between the vcc and the uvc, so two chatterbox...

And I am fully supportive of: 'if it works, don't change it' !
Eric